Process of manufacturing flutes



F. HOFINGER PROCESS OF MANUFACTURING FLUTES File??. 1 1922 rm fi-bias Patented May 15, 1923.

UNITED STATES FLORENT HOFINGER, OF BRUSSELS, BELGIUM.

PROCESS OF MANUFACTURING FLU'IES.

Application filed February To, all whom it may concern:

Be it known that I, FLoRnN'r Hormone, a subject of the King of Belgium. residing at No. 24% Rue de lIntendant lviolenbeek, St. Jean, Brussels, Belgium, h vs r ade certain new and useful Improvements in Processes of Manufacturing Flutes, oi which the following is a specification.

This invention relates to the art 01 producing musical instruments and it has more particularly for its object improvements in the manufacture of metal flutes.

litherto the various holes in the fiute have been surmounted each by a nozzle or neck soldered directly on to the body tube of the flute. A later improvement consisted in forming the said nozzles or necks by pressing-up the metal of the body tube. That method has over the earlier method the advantage of avoiding leakage due to faulty soldering. Both those methods have however two serious drawbacks as regards the proper action of the instrumeiit.

1. The nozzles have a sharp edge which has the effect of damaging the keys after a short period of use.

2. The tuning of the instrument is a difiicult matter because the various nozzles have to be milled to the correct height.

The present invention obviates those drawbacks by providing nozzles (or necks) with a flange integral therewith and substantially at right angles to the said nozzles so as to provide a flat annular surface on which the keys can rest.

These desired features are obtained by first pressing-up into a conical nozzle the edge of an oblong hole previously pierced in the body tube, and then converting said conical nozzle into a cylindrical nozzle with an inwardly turned annular flange having a fiat face or edge and finally milling the inner edge of the said flange to the desired inter nal diameter. For carrying out these various operations use is made of various tools whose natures and modes of action are fully described hereinafter with reference to the accompanying drawings in which Figure 1 is a view of a flute body tube showing the holes formed by the first milling.

Figure 2 illustrates in longitudinal section and cross section the mandrel upon which the flute tube is mounted during the performance of the various operations for Serial No. 537 .074.

les into the desired nozzles converting the ho or necks.

gures and l are views of the two conicylindrical dies respectively for efthe ressing-up of the metal.

5 illustrates the pressing-up to be shaped, there is placed the matrix 9 of which the aperture is formed with shouldered recess 10 correspending to the cylindrical flange t that is to constitute the nozzle (Fig. 9). The inner cavity of this matrix corresponds exactly to the periphery of the body tube 1.

The conical die 7 and the cylindrical die 8 fitting in a removable manner in the recesses 6 of the mandrel 5, are drawn towards the outer ends of these recesses by any suitable tractor member such as the bar 11 whose screw-threaded end 12 can be screwed into the correspondingly tapped holes in the dies 7 and 8.

According as either the conical die 7 or the cylindrical die 8 is drawn outwards by means of the bar 11, the metal at the edge of the body tube 1, will be pressed-up in the form 0% a conical nozzle d. Later, this conical nozzle is pressed-up in the form of a cylindrical nozzle 42 terminating in annular rlange 3 substantially at right angles to the id nozzle. The latter is then milled internally to the desired dimension 3 (Fig. 9) so that the finished nozzle has the appearance of: a cylindrical neck 2 having the height l. and the same diameter as that of the flange 3.

Since the pressing-up performed by means of the cylindrical mandrel is effected completely in the matrix 9, the nozzles will all have the same height 4;, thereby facilitating the tuning of the instrument. The nozzles (or necks) will not have any sharp edge Whatever, which is a very important feature for the length of the life of the padding on the keys.

The improved instrument has a perfectly finished appearance, and entails scarcely any upkeep costs; it can be easily tuned, because the sole milling required for tuning, is the milling of the internal diameter of the holes, that is to say, of the flange 3'.

What I claim is 1. A process for the manufacture of flutes formed of metal consisting in first forming oblong holes in the body tube of said flute, then pressing up the metal of the edges of said oblong holes so as to form conical nozzles, and then pressing the said conical nozzles into cylindrical nozzles with inwardly turned flanges integral therewith and substantially at right angles to the said cylindrical. nozzles so as to provide a flat annular surface on which the keys can rest.

2. A process for the manufacture of flutes formed of metal consisting in first forming oblong holes in the body tube of the said flute, then pressing up the metal of the edges of said oblong holes so as to form conical nozzles, and then pressing the said conical nozzles into cylindrical nozzles with inwardly turned flanges all at the same height above the said body tube and substantially at right angles to the said cylindrical nozzles.

3. A process for the manufacture of flutes formed of metal consisting in first forming oblong holes in the body tube of the said flute, then pressing up the metal of the edges of said oblong holes by means of dies to form conical nozzles, then pressing the said conical nozzles into cylindrical nozzles with inwardly turned flanges integral therewith all at the same height above the body tube, and then milling the edges of said inwardly turned flanges to obtain the correct diameters for tuning purposes.

In testimony whereof I have signed my name to this specification.

FLORENT HOFINGER.

Vitnesses FELIX DE COSMAN, G. G. ZOLRAN.

' mea 3' 

